The servers on the market at present generally can be divided into blade servers and single servers to meet different users' requirements. Structure wise, a blade server has multiple power slots to supply power for multiple main boards. A single server has only one set of power transmission line to supply power for one main board.
To users of the single server, when there is a need to add only one or two main boards, due to space constraint of the power supply of the original single server the additional main boards cannot get required power from the power supply of the original single server. Hence a blade server has to be used to provide the required power for the additional main boards. This involves altering the server chassis, power supply, etc. Not only the cost increases, the original single server also becomes useless. The substituted blade server also has extra power slots that are not fully used and become waste.